Method for removing excess aldehydes

ABSTRACT

An improvement in rapid reversal color photoprocessing is disclosed for removing excess free aldehyde compounds from photoprocessing solutions by contacting the aldehyde compounds with bisulfite ion.

United States Patent Inventor Donald J. Forst Webster, NJ-l.

App]. No. 19,491

Filed Mar. 13, 1970 Patented Jan. 11, 1972 Assignee ltek Corporation Lexington, Mass.

METHOD FOR REMOVING EXCESS ALDEl-IYDES 5 Claims, No Drawings US. Cl 96/22, 96/55 Int. Cl G03c 7/00, G03c 5/50 Field of Search 96/22, 55

[56] References Cited UNITED STATES PATENTS 3,168,400 2/ l 965 Blackmer et al 96/22 2,475,134 7/l949 Harsh et al 96/22 Primary Examiner-Norman G. Torchin Assistant Examiner-Alfonso T. Suro Pico Attorneys-Homer 0. Blair, Robert L. Nathans and David E.

Brook ABSTRACT: An improvement in rapid reversal color photoprocessing is disclosed for removing excess free aldehyde compounds from photoprocessing solutions by contacting the aldehyde compounds with bisulfite ion.

METHOD FOR REMOVING EXCESS ALDEHYDES BACKGROUND OF THE INVENTION 1. Field ofthe Invention This invention relates to the removal of excess free aldehyde compounds from rapid reversal color photoprocessing solutions.

2. Description of the Prior Art Aldehyde compounds are often present in photoprocessing solutions. For example, in the rapid reversal processing of color films, aldehydes are used to harden the sensitive hydrophilic colloid layers subsequent to first development to allow further processing at elevated temperatures without concomittant emulsion damage. Rapid reversal color processes are described in more detail in my copending application: U.S. Ser. No. 699,576, filed Jan. 22, 1968, now U.S. Pat. No. 3,447,741. It has been found, however, that even the presence of small amounts of excess free aldehyde compounds results in very serious difficulties in subsequent film processing steps. This problem is believed to be caused by a reaction under alkaline conditions between the excess free aldehyde compounds and some or all ofthe dye couplers present in the color emulsions, thereby destroying good color balance in the processed film.

One solution to this problem has been proposed in Blackmer et al., U.S. Pat. No. 3,168,400. This patent teaches that harmless addition products can be formed by reacting the excess free aldehyde compounds with primary amine compounds which have a hydroxyl, carbonyl or amino group attached to the primary amine radical. These primary amines, however, have proved to be relatively expensive, in addition these primary amine compounds are often in short supply and difficult to obtain.

SUMMARY OF THE INVENTION The invention is the improvement comprising the use of bisulfite ion to remove excess free aldehyde compounds from photoprocessing solutions. These bisulfite ions react with any excess free aldehydes present to form addition products which are harmless from a photoprocessing point of view.

The use of bisulfite ions offers the advantages of making the removal of excess free aldehydes economically feasible, simple but reliable. Additionally, the use of bisulfite neutralizers allows the elimination of the heretofore used chemical fogging agent t-butylamine borane in rapid reversal color processes because the bisulfite itself will act as a chemical fogging agent. This offers several significant further advantages since t-butylamine borane is both expensive and toxic, and since aldehyde neutralization and chemical fogging can be carried out simultaneously.

DESCRIPTION OF THE PREFERRED EMBODIMENTS There are many photoprocesses wherein aldehydes are used early in the processing sequence. In most of these, it is necessary and/or advantageous to remove any excess free aldehyde compounds before subsequent processing steps are initiated. This is particularly true in the processing of color films, because the free aldehydes react with certain dye formers present in the color emulsions. When this happens, it is virtually impossible to obtain good color balance in the processed film.

Some examples of aldehydes used in reversal color processing include: dialdehydes, especially glutaraldehydes such as glutaraldehyde; beta methylglutaraldehyde; alpha, alphadimethylglutaraldehyde; alphamethylglutaraldehyde; and alpha, beta dimethylglutaraldehyde; monoaldehydes such as succinaldehyde, formaldehyde; and combinations ofthese.

It has been found that excess free aldehyde compounds can be removed It can be found that excess free aldehyde compounds can be removed by contacting the aldehydes with bisulfite ion. Bisulfite ion can be obtained from many sources, including but not limited to solutions of soluble sulfite compounds. Some examples of such soluble sulfite compounds include: inorganic sulfites such as sodium sulfite; organic sulfites such as ethane disulfonic acid; metabisulfites such as sodium metabisulfite; and bisulfites such as sodium bisulfite. A preferred source of bisulfite ion is aqueous solutions of alkali metal bisulfites, especially sodium bisulfite.

When aqueous solutions of sulfites or metabisulfites are used, it is preferable to control the pH of the solution so that it is neutral or acidic so that adequate quantities of the bisulfite ion will be generated.

In general, the amount of bisulfite ion used will depend upon the amount of excess free aldehyde to be removed. To remove all of the excess free aldehyde, of course, will require that the bisulfite ion be added on a molar basis. Since the amounts of excess free aldehydes are usually low, normally from about 0.1 percent to about 10 percent of a bisulfite compound by weight dissolves in solution is adequate. Preferably,

the amount is about 1 percent dissolved bisulfite compound.

The invention is further illustrated by ples.

EXAMPLE I the following examman Kodak Ib sensitometer with a Cornin filter, to a 2l-step carbon wedge for 1/25 second. After expog 5900 daylight sure the strip is processed with the following solutions:

Develo er:

Quadrafos 2.0 g. Phenidone 1.0 g. Sodium Sulfite (anh) 50.0 g. Methylhydroquinone 7.0 g. Ethylenediamine (93%) 26.0 ml. Sodium Thiocyanate 1.0 g. Boric Acid 12.0 Potassium Iodide (0.1% soln) 13.0 ml. 1-phenyl-2-tetrazoline-5-thione 5.0 ml. (0.5% soln) Water to make 1.0 1. Stop Bath:

Sodium Sulfate 100.0 g. Acetic Acid (glacial) 20.0 ml. Sodium Acetate (BH O) 10.5 g. Water to make 1.01. Hardener:

Glutaraldehyde (25% solution) ml. Sodium Sulfate (anhydrous) g. H O in 1.0 1. pH 4.0 Neutralizer:

Sodium Bisulfite Water Color Developer:

Ouadrafos 5.0 g.

Benzyl Alcohol 15.0 ml. tert-butylamine borane 0.28 g. Sodium Sulfite (anh) 7.5 g. Sodium Phosphate (tribasic) 40.0 g. Sodium Bromide 0.9 g. Potassium Iodide (0.1%) 31.0 ml. Citrazinic Acid 3.6 g. 4 amino-N-ethyl-N-( belamethanesulfon- 13.0 g. amidoethyl)-m-Toluidine, sesquisulfate monohydrate Sodium Hydroxide 7.5 g. H,O to 1.0 1. pH 12.0 Clearing Bath:

Potassium metabisulfitc 40.0 g. H O to 1.0 1. Bleach:

Sodium Bromide 26.0 g. Sodium Ferrocyunide [OH- .0 18.0 g. Potassium Persulfate 51.0 Sodium Phosphate (dibasic anh) 12.5 Carhowax I540 (50%) 6.0 ml. 11,0 w 1.0 pH 7.8 Fixer:

Sodium Sulfite 10 g. Sodium Thiosulfate (5H,O) 250 g. Ammonium Sulfate 50 g. Stabilizer:

Formalin Solution 10 m1. X Ethylenediamine tetraacetic-acid 1 I 10.0 g.

(Tetra sodium salt) Water to make 1.0 l.

The reversal processing sequence is:

Developer 75 F. for 2 minutes Stop Bath 75 F. [or 30 seconds Hardener 100 F. for 30 seconds Neutralizer 100" F. for 1 minute Color Developer 100 F. for 8 minutes Clear 100" F. for 30 seconds Bleach 120 F. for 2 minutes Fixer l20 F. for 1 minute Wash 120 F. for 2 minutes The sodium bisulfite neutralizer is used in amounts of 0.1 percent, 1.0 percent and 10.0 percent. In each case, excellent color balance is maintained in the processed film which indicates that the excess free aldehydes remaining in the film after the hardening step are neutralized.

EXAMPLE 11 The film, exposure conditions, processing solutions and processing sequence are the same as in example I except that the neutralizer comprises a 10 percent aqueous solution of sodium metabisulfite (Na S O The processed film displays excellent color balance.

EXAMPLE Ill The film, exposure conditions, processing solutions and processing sequence are the same as in example I except that a percent aqueous solution of sodium sulfite (Na- 80 is used as the neutralizer. Two runs are made. The first at a neutralizer pH of seven results in a processed film with a maximum density in the magenta dye decreased 0.2 density units. The second run with the neutralizer pH adjusted to 3.1 with sulfuric acid results in a processed film having excellent color balance with no loss of density.

EXAMPLE IV The film, exposure conditions, processing solutions and processing sequence are the same as in example 1 except that the neutralizer comprises a5 percent aqueous solution of ethane disulfonic acid adjusted to a pH of 3.1 with sulfuric acid. The processed color film had excellent color balance.

EXAMPLE V Developer 75 F. for 2 minutes Stop Bath 75 F. for 1 minute Hardener F. for l minute 10% Sodium Metuhisulfite 100 F. for 1 minute Water Rinse Color Developer 100 F. for 8 minutes Clear l00 F. for l minute Bleach 100 F. for 4 minutes Fixer 100 F. for 2 minutes Wash 100 F. for 5 minutes All operations are carried out in total darkness up to the bleach step to prevent fogging.

Sensitometric results and color balance are equivalent to those obtained in example I where a chemical fogging agent was present in the color developer.

Other embodiments will occur to those skilled in the art and are within the scope of the following claims.

What is claimed is: 1. 1n the reversal processing as color films, the improvement for removing excess free aldehyde compounds from the film prior to color development comprising contacting said aldehyde compounds with bisulfite ion under neutral or acidic conditions.

2. The improvement of claim 1, wherein said aldehydes are contacted with a solution containing an inorganic bisulfite compound.

3. The improvement of claim 2 wherein said inorganic bisulfite compound is present as an aqueous solution containing between about 0.1 and about 10 percent bisulfite compound on a weight basis.

4. The improvement of claim 3 wherein said inorganic bisulfite compound comprises an alkali metal bisulfite compound.

5. The improvement of claim 4 wherein said inorganic bisulfite compound comprises sodium bisulfite.

UNITED STATES PATENT OFFICE v CERTIFICATE OF CORRECTION Patent No. 3,634, 081 January 11, '197z lnvento'fls) Donald J. Forst It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, lines 16 and 1.7, delete "now U.S. Pat. No. 3,447,741." and insert therefor now abandoned.

Col. l, lines 70 and 71, delete the following sentence, "It has ,been found that excess free aldehyde compounds can be removed.";

Col. 1, line 72, cancel between the words "It" and "found" the words "can be and insert the words has been Col. 2, line 76 delete "X" before the words "Ethylenediamine tetraac'etic-acid" and change "11 10.0 g." (second column) to 10.0 g.

Col. 3, line 2, delete "l.0l." and insert in line 1, second column therefor 1.0 liter.

Col. 3, line 8, in the first column after "Color Developer", move "100F." to the second column.

Signed and sealed this nth day of July 1972 (SEAL) Attest:

EDWARD I LFLETCHER, JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM PO-1050 (10-69) USCOMM-DC 60376-P69 h u.s. GOVERNMENT PRINTING OFFICE: I969 o-aes-su 

2. The improvement of claim 1, wherein said aldehydes are contacted with a solution containing an inorganic bisulfite compound.
 3. The improvement of claim 2 wherein said inorganic bisulfite compound is present as an aqueous solution containing between about 0.1 and about 10 percent bisulfite compound on a weight basis.
 4. The improvement of claim 3 wherein said inorganic bisulfite compound comprises an alkali metal bisulfite compound.
 5. The improvement of claim 4 wherein said inorganic bisulfite compound comprises sodium bisulfite. 